Bleeder turbine



July 6,1926; 1,591,486-

I. S. HANSON BLEEDER TURBINE Filed Jan. 20,1923 3 Sheets-Sheet 1 I w "I'll lullllllllllx WITNESS- INVENTOR ATTORNEY July 6 1926. 1,591,486

I. s. HANSON BLEEDER TURBINE Filed Jan. 20, 1923 3 Sheets-Shet 2 5% 56 l fl INYENTOR ATTORNEY July 6,1926. 1,591,486

' l. S. HANSON BLEEDER TURBINE Filed Jan. 20, 1925 s SheCS-Shee t 3 v WITNE F -7- INVENTOR I ATTORNEY Patented July 6, 1926.

- UNITED STATES 1,591,486 PATENT OFFICE...

IVAN S. HANSON, OF WINTER HARBOR, MAINE, ASSIGNOR TO VfESTINGI-IOUSE' ELEC- TRIO AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

. BLEEDER TURBINE.

Application filed January 20, 1923. Serial No. 613,986.

My invention relates to bleeder turbines and it has for its object to provide apparatus of the character designated which shall be capable of maintaining an approximately constant bleeder pressure under widely varying operating conditions.

A further object of my invention is to provide, in connection with apparatus of this character, an improved bleeder control mechanism which shall be positive in its action and which shall be subject to small variations of bleeder pressure in order to maintain the bleeder pressure approximately constant.

A still further object of my invention is to interconnect the main turbine governor with the bleeder control mechanism, so that, uponextreme conditions of underload, the supply of steam to the low-pressure section of the turbine shall be restricted or entirely cut off, and, so'that, upon a predetermined overload, the supply of steam to the bleeder connection shall be restricted and the supply of steam to the low-pressure section shall be increased, and, upon an extreme condition of overload all of the steam discharged from the high-pressure section shall flow to the low-pressure section. The feature of governor inter-connection is particularly desirable as it avoids the possibility of the turbine racing due to the action of the bleeder head on the low-pressure section when the supply of steam to the high-pressure section is cut off when shutting the turbine down. A further object of my invention is toreceive such a direction of discharge from the high-pressure section that the turbine may be made relatively short and of a relatively simple construction.

Apparatus embodying features of my invention is illustrated in the accompanying drawings, forming a part of this application, in which: 7

Fig. 1 is a side elevation of a turbine with my improved bleeder mechanism applied thereto; i

Fig. 2 is a sectional view taken along the line IIII of Fig. 1;

Fi 3 is a detail view, partially in section and rawn to a larger scale, of the bleeder valve operating mechanism;

Fig. 4 is a detail sectional view showing the butterfly bleeder valve, its housing, and its relation to the turbine;

Fig. 5 is a perspective view of the butterfly valve and a part of its operating piston; Fig. 6 is a diagrammatic view showing the operative relation of all essential parts;

F1g. 7 shows a modified form of turbine to which my invention may be applied.

Referring to the accompanying drawings for a more detailed description of my invention, I show a bleeder turbine, at 10, including a high-pressure section '11, preferably of the multi-velocity type, and a low-pressure section 12, preferably of the fractional expansion type, separated by a diaphragm 13 connected to the turbine casing 14 and having a gland fit with respect to the rotor 15. See Figs. 4; and 6.

A bleeder connection or conduit 16 is connected to the turbine casing in a manner to be described and steam is supplied to the.

high-pressure section by means of any suitable valve arrangement, at 17 under the control of a governor at 18.

It is a characteristic feature of my improved turbine that steam does not flow from the high-pressure section 11 to the lowpressure section 12 within the turbine casing; but, after passing through the blading of the high-pressure section, the steam is deflected by the diaphragm 13 and it passes around to the front of the blading to what may be termed the discharge chamber 19 for the high-pressure section from whence the steam is conducted to either or both the lowpressure section 12 and the bleeder line or conduit 16 in the manner to be described.

Communication between the discharge chamber 19 of the high-pressure turbine section 11 and the low-pressure turbine section 12 and the bleeder line or conduit 16 is afforded by means of a three-way passage provided by a casing 20 secured to the turbine casing 14 and fitting over the openings 21 and 22, communicating, respectively, with the ch amber 19 and with the inlet side of the low-pressure section 12. The casing 20 has a chamber portion 23 which communicates with the bleeder line or conduit 16.

' A butterfly valve 24 is arranged within the chamber for the purpose of controlling the flow of steam passing from the opening 21 both to the opening 22 and to the bleeder line chamber 23. The wings of the valve are adapted to cooperate with inwardly-projecting, arcuate seats 25 and 26 carried by the iii) casing 20 and with diagonally-opposed plane seats 27 and 28 provided by the exterior of the turbine casing 14.

Upon reference to Figs. 4 and 6, it will be seen that the valve 24 is me *able in one direction to cut oil? the supply of steam to the low-pressure turbine section 12 and to open up communication with the bleeder line chamber 23, while movement of the valve in the other direction results in closure of communication of the high-pressure section with the bleeder line and the opening up of communication thereof with the lowpressure turbine section.

Upon reference to Fig. 5, it will be seen that the bleeder valve 24 is provided with upper and lower trunnions L9 and 30 which are ada'ptedto be journ'aled in the casing 20, the upper trunnion extending above the casing and being provided at its upper end with a pinion 31 which meshes with a rack 32 carried an og ierating piston 33 arranged within the operating cylinder of the fluid relay, at 35.

The fluid relay includes a suitable pilot valve '36 for controlling the admission and exhaust of motive fluid to the ends of the operating cylinder 34 to secure actuation of the operating piston 33.

The pilot valve 36 ismoved in response to changes in pressure in the bleeder line in order to secure actuation oi. the butterfly valve 24 in such directions as to result either in a decrease or an increase of steam to the blceder line so as to maintain an approximately constant bl'eeder line pressure. p

The pilot valve 36 is also connected to the governor. at 18, so that, upon extreme move ments of the latter. due to overloads or to shutting down ofthe turbine, the butterfly valve is moved to supply more stean. to the low-pressure section or to cut oil communication between the low-pressure section and the bleeder line.

The pressure-responsive device is preferably of the diaphragm type. shown at 37, and it is connected to the ble'eder line or cond'uit 16 by means of a conduit or passage 39. The diaphragm is connected to a floating lever 41 pivotally connected to a link or stem 42 carried by the pilot valve 36.

The connection between the diaphragm and the floating lever includes any suitable means for imposing a iegiulable pressure against the diaphragm in opposition to the fluid pressure applied thereto. For example, I show a lever 43 fulcrumed at 44, pivotally connected at 45 to a stem 46 carried by the diaphragm 37 and carrying an adjustable weight device 47. It will, therefore, be seen that by adjusting the weight 47 the pres sure at which movement of the diaphragm may take place in opposition to the weight may be varied. V p

One end of the floating lever 41 is connected to the lever 43 by a link 48 while the other end 01 the floating lever is pivotally connected to a link or rod 49 which has its lower end fitting against a wedge or cam 51 carried by the opening piston 32. A weight 52 is preferably carried by the floating lever 41 in order to maintain the lower end of the link or rod 49 in contact with the wedge or cam 51.

As soon 'as a change in pressure in the bleeder line takes place, the diaphragm of the pressure-responsive device 37 moves either up or down as the case may be and the latter movement results in movement the floating lever 41 and the pilot valve 36 so as to secure the admission and exhaust of motive fluid to the operating cylinder 34 for the purpose of moving the piston 33 in such adirection as to provide for movement of the butterfly valve '24 to moditythe flow of steam to the bleeder liii'ein such a way as to maintain the blender line pressure approximately constant. Ii the blceder line pres sure should begin to decline, the butterfly valve 24 innnediately moves to supply more steam to the bleeder line, and, if the bleeder line pressure should start to increase above the predetermined pressure, the butterfly valve immediately moves 'to restrict the i'low of steam to the bleeder line. VVh'e'never the operating piston moves, the cam or wedge 51 thereof results either in upward or downward movement of the floating lever 41 about its pivot with respect to the link 48 so as to bring the pilot valve 36 back to a neutral or cut oil position. v

The governor, at 18, is connected to the lever 41 by any suitable linkage including a lost-motion device so that it is e'ii'ective to move the floating lever only at extreme positions thereof. For example, I show upper and lower stops 54 and 55 carried by a link 56 which is moved up and down by the governor at18.

In Fig. 6, I Show, in diagrammatic form, all the essential parts arranged to operate in accordance with my invention. In order to avoid crossing of piping in the drawing and in order to more clearly explain the operation thereof I show the inclination of the cam or wedge member 51 as reversed from that shown in Figs. 3 and 5. I also show the link 56 with the steps 54 and 55 arranged to moveoppositely to the actuating movement imparted by the governor 18 whereas in Fig. 1 it moves in the same direction; It -will be apparent, however to those skilled in the art that the operation about to be described is secured by either the arrangement illustrated in Figs 1 to 5 inclusive or by that described in Fig. '6.

If, as shown in Fig. 6, the link 56 should move downward dueto an increase in speed, the stop 54 would finally come in contact with the floating lever 41 and move the hit ter, together with the pilot valve 36, downwardly, in which case, fluid under pressure would be admitted to the left-hand end of the operating cylinder 34 with the result that the butterfly valve 24 would move in a clockwise direction looking downwardly thereon to diminish the supply of steam to the lowpressure section 12 and to increase the supply to the bleeder line 16. When shutting the turbine down, the link 56 would move up in response to movement of the governor, with the result that the pilot valve 36 is moved up and the operating piston is moved toward the left and the butterfly valve 24 is operated in a counterclockwise direction to cut ofl communication between the bleeder line and the low-pressure turbine section, thereby avoiding overspeeding of the latter under the head of the bleeder line pressure. V

In Fig. 7, I show a modified form of turbine in which the direction of flow in the high-pressure section is opposite to that heretofore described, that is, the nozzles of the high-pressure section 11 are arranged between the diaphragm 13 and the blading with the result that the steam enters the discharge chamber 19' without reversal. Otherwise, the structure shown in Fig. 7 is similar to that heretofore described.

From the foregoing, the operation of apparatus made in accordance with my invention will be apparent. Whenever a change takes place in thebleeder line pressure due either to an increased or decreased bleeder demand, the diaphragm 37 of the pressureresponsive device moves the floating lever 41 so as to secure actuation of the fluid relay with the result that the operating piston is moved in such a direction as to change the position of the butterfly valve 24 so that the How of motive fluid to the bleeder line is suitably modified in order to maintain an approximately constant bleeder line pressure.

As soon as the operating piston 33 begins to move, the floating lever is actuated by the wedge or cam 51 in order to bring the pilot valve back to a neutral or cut off position. As shown in Fig. 6, movement of the cam 51 toward the right results in the lever 41 being pushed up while movement toward the left requires that the link 49 and the lever 41 shall be pulled down in'order that the lower end of the link 49 may at all times contact with the cam 51. The weight 52 is, therefore, provided for this purpose.

As already pointed out, extreme positions of the governor 18 result in the actuation of the operating piston 33 for the purpose of moving the butterfly valve 24 either to out off the supply of steam to the low-pressure section or to cut 0E communication between the low-pressure section and the bleeder line.

While I have shown my invention in but two forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claims.

hat I claim is:

l. A bleeder turbine comprising high and low-pressure sections, a diaphragm for segregating the sections, a bleeder connection, a three-way passage comn'iunicating with the exhaust of the high-pressure section, with theinlet of the low-pressure section, and with the bleeder connection, and a butterfly valve in the passage which, in one extreme position, closes communication between the high and low-pressure sections, in the other extreme position, closes communication between the high-pressure section and the bleeder connection, and in in tcrmediate positions controls the division of motive fluid passing to the bleeder connection and to the low-pressure section.

2. The combination witha bleeder turbine having a casing enclosing high and lowpressure sections and being provided with ports which communicate with the exhaust end of the high-pressure section and with the inlet of the low-pressure section, of a valve chamber structure secured to the easing and covering said ports and being provided with seatswhich are diagonally opposed to the seats provided at opposite sides of the port communicating with the lowpressure section, a bleeder connection connected to the valve chamber between its seats, and a butterfly valve arranged in the chamber and adapted, in extreme positions, to be seated on the diagonally-opposed seat-s to cut off communication either with the bleeder connection or with the low-pressure section and, in intermediate positions, to divide the motive fluid discharged from the high-pressure section between the low-pressure section. and the bleeder connection.

3. The combination with a bleeder turbine having high and low-presure sections, a bleeder connection, and a valve for control ling the flow of steam from the high-pres- Lil) lit":

sure sectionto the low-pressure section and to the bleeder connection, of an operating cylinder, an operating piston structure connected to the valve so that movement of the piston structure is transmitted to the valve, a pilot valve for controlling the admi. ion and exh'ziust oi motive fluid to op p'osite sides of said piston structure, a pressure-responsive device connected to the bleeder connection a floatinglev'er connecting the pressare-responsive device and the pilot valve sothat the latter may move to admit motive liui'd to either side of said op erating piston structure to move the bleeder valve upon an increase or decrease of pressure in the bleeder connection, a cam car ried by said piston structure, and a connection between the floating lever and the cam,

so that, when the piston structure moves in response to the admission of motive fluid to the operating cylinder consequent upon movement of the pilot valve, the pilot valve is brought back to a neutral or cut-oli position.

el. The combination with a bleed cr turbine having high and low-pressure sections with means for segregating the sections, of ports in. the turbine casing communicating with the high and low-pressure sections, a valve housing for covering the ports, a bieeder connection communicating with the housing, a butterfly valve in the housing arranged to cut oif communication of the high-pressure section with the low-pressure section or with the bleederjconnection or to divide the motive fluid discharged from the high-pressure section between the low pressure section and the bleeder connection, a motor device for moving the butterfly valve, a pilot valve for admitting motive fluid to the motor device, aapressure-responsive device connected to the bl'eeder connection for moving the pilot valve, and means dependent upon the movement of the motor device to bring the pilot valve back to its neutral or cut-ofl position.

5. The combination with a bleeder turbine having a casing enclosing high and lowprcssnre sections separated by a diaphragn i, of a discharge port in the casing communicating with the high-pressure section, an inlet port in the casing communicating with the low-pressure section, a valve housing secured to the casing and covering said ports, a bleeder connection communicating with said valve housing, the housing and the inlet port being so relatively disposed as to define diagonally-opposed valve seats, a butterf'lv valve in the housing arranged to cooperate with the valve seats and adapted, in extreme positions, to cut oit communica tion of the high-pressure section with the lowpressure section or with the bleeder connection, and, in intermediate positions, to divide the steam discharged between the low-pressure section and the bleeder connection, a motor device for moving the valve, and a pressare-responsive device connected to the bleeder connection for controlling the motor device so that the batten il y valve is moved to maintain an approxi mately constant bl'eeder pressure under variable conditions of operation.

6. The combination with a bleeder turbine having high and low-pressure sections, of a. bleeder connection, a valve for controlling the how of steam from the high-pressure section to the lown'cssurc section and to the bleeder connection, admissioil-valve mecha-- nism for the high-pressure section, governor mechanism for controlling the admission valve, a motor device "for moving the bleeder valve to control the passage oimotive llni'l from the high-pressure section to the bleed er connection and to the low-pressure section, means for controlling -the operation of the motor device which is dependent upon the pressure in the bleeder connection, and a connection between said governor mechanism and said controlling means so that, upon overloads beyond a predetermined extent, the bleed'cr valve is operated to establish more completely con'nnunication of the liiglipresstn'e section with the low-pressure section and, upon un'derloads below a predetermined extent, communication between the liiglnpre'ssure section and the bleeder connection is established more completely.

7. In a bleeder turbine, the combination of a casing, a high-pressure section spaced from one end of the casing to define a dis charge chamber for the high-pressure section, a lmv-pressurc section, a diaphragm separating the sections and closing con'nnunication therebetweenwithin the casing, a bleeder connection, a three-Way passage for connecting said chamber with the inlet end of the low-pressure section and with the blecder connection, a butterfly valve in the passage forcontrolling the flow of motive fluid from the chamber to the low-pressure section and to the bleeder connection, and pressure-responsive means carried by the connection and operating to adjust the butterfly valve to maintain an approximately constant bleeder pressure.

8. A' bleeder turbine comprising a high pressure section having an admission valve, a low pressure section, a diaphragm dividthe sections, a valve casing connecting; the sections, a bl'eeder conne'ction connected to the valve casing, a bleeder valve within the valve casing controlling communication between the high pressure section and the low pressure section and between both sections and the bleeder connection, a speed responsive governor for controlling the adn'rission valve, a pressure responsive device connected. to the bleeder line, relay mechanism normally controlled by the pressure re- You sponsive device for operating the bleeder valve, and means actuated by the speed responsive governor and efiective upon a predetermined reduction in speed of the turbine to control the relay and cut off communication between the bleeder connection and both the turbine sections.

9. A bleeder turbine comprising a high pressure section having an admission valve, :1 low pressure section, a diaphragm dividing the sections, a valve casing connecting the sections, a bleeder connection connected to the valve casing, a bleeder valve within the valve casing controlling communication between the high pressure section and the low pressure section and between both sections and the bleeder connection, a speed responsive governor for controlling the admission valve, a pressure responsive device connected to the bleeder line, relay mechanism normally controlled by the pressure responsive device for operating the bleeder valve, and means including a lost motion connection between the speed responsive governor and the relay mechanism, whereby upon a predetermined reduction in speed of the turbine the speed responsive governor actuates the relay and communication between the bleeder connection and both the turbine sections is cut off.

In testimony whereof, I have hereunto subscribed my name this 6th day of Jan.,

, IVAN S. HANSON. 

